To evaluate whether a 2 year exposure to an electromagnetic field equivalent to that generated by cellular phones can accelerate tumor development in the central nervous system of rats (brain tumorigenesis was initiated by an intrauterine exposure to N-ethylnitrosourea on gestational day 18).
Modulation type: pulsed
Exposure duration: repeated daily exposure, 90 min/day, 5 days/week for 104 weeks
|Distance between exposed object and exposure source||30 mm|
|Chamber||The exposure box was 90 x 90 x 60 cm, the inside walls except for the ceiling being covered with electromagnetic absorber. Ten boxes were used simultaneously.|
|Setup||Ten rats, fixed individually in plastic tubes (four different sizes), were set on a disk-shaped plate (65 cm in diameter) with their nose towards the center. A quarter-wavelength monopole antenna on the ceiling of the exposure box fitted in the center of the disk-shaped plate. The distance between the antenna and each rat nose was 30 mm and the distance between the ceiling and the rat back was 5 mm.|
|Additional info||Plastic holders used were of four different sizes (inner diameter 4.0 cm, 4.7 cm, 5.5 cm, and 6.2 cm). If rats deceased, dummy rats were used to maintain symmetry and scheduled SAR in the exposure box.|
|SAR||2 W/kg||average over mass||measured and calculated||brain||-|
|SAR||6 W/kg||peak value||measured and calculated||brain||time peak|
|SAR||0.67 W/kg||average over mass||measured and calculated||brain||-|
|SAR||2 W/kg||peak value||measured and calculated||brain||time peak|
|SAR||0.4 W/kg||average over mass||estimated||whole body||-|
There were no differences between the groups in body weights, food consumption, and survival rates. No increase in the incidences per group of brain and/or spinal cord tumors, either in the males or females, was revealed in the exposed rats. Additionally, no clear changes in tumor types were evident.
In conclusion, under the present experimental conditions, 1.439 GHz electromagnetic field exposure to the heads of rats for a 2 year period was not demonstrated to accelerate or affect N-ethylnitrosourea initiated brain tumorigenesis